Patent literature 1 discloses a charging system for a vehicle having a timing function so that charging can be reserved, in which even though the timing function is abnormal, charging can be started at a reserved charging start time as much as possible. In the charging system for a vehicle, upon occurrence of abnormality in the timing function of a timing function section, a control section determines whether start-up can be continued in a normal mode until the charging start time based on the residual power of a 12 V battery and its own power consumption. When it is determined that the start-up can be continued, the charging start time is waited in the normal mode.
Patent literature 2 discloses a load leveling system in which each battery of a plurality of vehicles is charged during non-peak power demand at a business place, which is a power consumer receiving electric power supplied from a power supply company, or by using midnight power of each vehicle owner, and the electric power stored in the charged vehicle battery is discharged during peak power demand at a business place.